Test it out on Pearl, claiming a simple material object

The card granted you represents a titanic once in a lifetime gift. It was addressed specifically to you too, wasn’t it? Wouldn't it be a huge waste to not take the one step required to verify the reality of your ‘ability’?

"Yu's right. I should test this out to see if it's legit," you say, after a moment’s thought. "Pearl? You mind if I try claiming something of yours?"

Pearl groans. "Of course I mind."

Yu's interest grows. "Actually Pearl's a good choice," she says, arranging herself to stand next to you, opposite Pearl. "Whether or not she minds shouldn't matter, but if she's unwilling, it'll be a good proof of concept. If you claim something of hers she doesn't want to give up, and Pearl surrenders it to you anyway, then we'll know it works."

"Good point," you say.

"Hello, do I get a vote?" asks Pearl.

“Sorry Pearl,” says Yu. “At least in this case it’s better that you don’t.”

Pearl scoffs. “Traitor.”

You point to Pearl's black jacket. "I'll claim that hoodie," you say, testing out your theoretical power. Is this real? No way everybody’s gone simultaneously crazy, right?

Pearl sighs in defeat and glances down at her hoodie. You hardly see her go anywhere without it. "Dammit. And I liked this hoodie too," she says. She gives you a half hopeful, half annoyed look. "Technically speaking it's yours now, Chase, but is it okay if I keep wearing it? I borrow stuff from you all the time. This'll just be a long-term loan. It wouldn't even fit you anyway."

Yu gives her friend a curious look. "Interesting. It seems like Pearl is rationalizing a way she can maintain the status quo even though it's your hoodie she's wearing now."

"It works," you say, clapping your hand to your forehead. You’re amazed. Not just at Pearl's reaction, but Yutong's. Both of them seem to believe Pearl's ubiquitous hoodie is yours now, despite that being utterly ridiculous.

You really can't believe it. Like, you knew it would work, subconsciously, but seeing it in action is different. And this is just the tip of the testing iceberg.

"Pearl, I know you'd rather keep wearing it, but could you hand me your - I mean, my hoodie?"

Grumbling, Pearl pulls the hoodie over her head and roughly shoves it into your arms. "There. Are you happy?"

Beneath the hoodie, Pearl's wearing an old and tightly-stretched Powerwolf band t-shirt. You always forget how buxom she is since she's always in loose clothing - that shirt didn’t used to be so tight when you were freshmen.

You look from the hoodie in your hands to Pearl, and back again."Wow. I didn't think you'd literally give me the coat off your back.”

Now grumpy, Pearl folds her arms over her chest and scowls. "You were listening when Yu read the card, didn't you? It's your jacket now. You claimed it," she says. "So now that we're done treating me like some kind of lab rat, can I have my hoodie back now? Like, as mine again?"

But Yu has other ideas. "Chase, don't forget. The card said you can claim anything, physical or immaterial. It obviously works on the physical, so why don't you try claiming something immaterial now?"